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Due to the significant pharmacophoric role of 1,4‐naphthoquinone moiety, which is found in numerous biologically active natural products and well‐known chemotherapeutic drugs, including doxorubicin, shikonin, and alkannin, a newly prepared ligand ((E)‐1‐((2‐mercaptophenyl)imino)naphthalen‐2(1H)‐one) can be obtained from the condensation of 2‐aminothiophenol with diketone (1,2‐naphthoquinone) to form Schiff base (HL), which has been characterized using elemental analyses, FT‐IR, 1H‐NMR, and mass spectra. The inner ((La(III), Er(III), and Yb(III)) and outer ((Fe(III), Co(II), and Zn(II)) transitionmetal complexes have been prepared in 1:2 ratio and identified by several spectroscopic instruments. Different characterization tools have been used as elemental analyses, 1H‐NMR, molar conductivity, 13C‐NMR, FT‐IR, thermal decomposition (TG and DTG), UV‐vis, X‐ray diffraction, mass spectrometry, solid reflectance, and magnetic moment. All of them are conjugated to confirm the proposed structures of the metal complexes and are complementary. Also, molecular docking studies for the ligand and its Zn(II) and Yb(III) complexes (using MOE program) have been performed to support the experimental biological activity. Molecular docking studies recommended that (Yb(HL)2)Cl3·6H2O complex is more potent against Aspergillus niger fungus when docked with 1Y43 (aspergilloglutamic peptidase enzyme from A. niger) receptor, while Zn(II) complex recorded the strongest binding energy among the docked compounds against 2W3Z(the crystal structure of a Streptococcus mutans CE4 esterase) and 7AB4 (the crystal structure of the Escherichia coli toxin‐antitoxin system HipBST [HipT S59A]) proteins receptors, respectively. Experimental applications of the free ligand and its metal chelates as antimicrobial and antioxidant activities have been carried out. The former occurred against two fungal species (Aspergillus niger [ATCC:16404] and Candida albicans [ATCC:10231]), two G‐positive bacterial species (S. mutans [ATCC:25175] and Staphylococcus aureus [ATCC:13565]) and two G‐negative bacterial species (Klebsiella pneumonia [ATCC:10031] and E. coli [ATCC:10536]). The DPPH scavenging method has been used to measure the antioxidant activity of the tested compounds. [ABSTRACT FROM AUTHOR]

Novel thiophene Schiff base ligand (L) was synthesized through the condensation of 2‐thiophene‐methylamine and 3‐formyl‐4‐methoxyphenylboronic acid. Transition metal complexes with the formulae [M(L)(H2O)2Cl]Cl2.xH2O (M = Er(III), x = 4 and La(III), x = 5) and [M(L)(H2O)Cl2]Cl.xH2O (M = Yb(III), x = 4 and Ru(III), x = 0) were synthesized. Different spectral and physicochemical methods were used to confirm and identify the stoichiometry, structure, and bonding style of transition metal chelates. The creation of 1:1 molar ratio (M:L) complexes was supported by elemental data. According to IR spectra, the thiophene Schiff base ligand (L) acted as a tridentate ligand that is neutrally coordinated by S‐thiophene, N‐azomethine, and o‐methoxy groups. All chelates formed in octahedral structures according to the findings data. Thermogravimetric analysis (TG and DTG) was employed to examine the heat decomposition of these compounds. DFT/B3LYP method, a molecular modeling methodology, is used to support the expected shape of the produced ligand. Chemical hardness and softness, HOMO and LUMO energy levels, electrophilic index, bond lengths, angles, dipole moment, electronegativity, and other factors were calculated. Against HepG‐2 cell line, the in vitro anticancer activity of all chelates and free ligands was evaluated. These synthesized compounds showed good effectiveness. Additionally, DPPH scavenging was used to assess antioxidant activity, with extremely positive results. Molecular docking with the hepatic protein receptor 3ELJ was used to confirm the anticancer results. Finally, the effectiveness of the current thiophene ligand's ability to block Al‐Si alloys in 1 M HCl solution was examined utilizing electrochemical methods. The high inhibition efficiency was obtained revealing the effectiveness of using this thiophene Schiff base ligand on an industrial scale. [ABSTRACT FROM AUTHOR]

The medication bromhexine (BHX) is well‐known for its unique properties and therapeutic advantages, with prospective uses in the prevention and treatment of cancer growth and bacterial infections. The current research describes the synthesis of a unique series of mixed ligand complexes of Cr(III), Fe(III), Ni(II), Mn(II), Cu(II), Co(II), Zn(II), and Cd(II) produced from BHX (1ry ligand) and 1,10‐phenanthroline (Phen; 2ry ligand) and distinguished by spectral. The two ligands' potential for coordination with metal ions has been suggested in view of chemical analysis and spectral (1H‐nuclear magnetic resonance, ultraviolet–visible, and mass spectrometry) and thermal studies. BHX and Phen are neutrally bidentately coupled to the metal ions, according to infrared spectral study. The general formula of [M(BHX)(Phen)(H2O)n.Clm] was suggested using the molar conductivity, elemental analyses, and thermal information of the complexes that were produced. Where M = Fe(III) (n = y = 2, m = 0, and x = 3), Co(II) (n = x = 2, m = 0, and y = 3), Ni(II) (n = x = 2, m = 0, and y = 6), and Cd(II) (n = x = y = 2 and m = 0) with an octahedral geometry was proposed. Thermal analyses revealed that the complexes lost anionic part and organic ligands in continual changes after first losing water molecules of hydration. Compared with their parent BHX ligand, the mixed ligand complexes demonstrated promising microbiological activities against a variety of bacterial species, including Gram‐positive bacteria (Bacillus subtilis and Staphylococcus aureus) and Gram‐negative bacteria (Escherichia coli and Pseudomonas aeruginosa). According to the results, mixed ligand complexes are more efficient than the parent BHX and Phen ligands. The complexes moderately inhibit the development of the MCF‐7 antibreast cancer cell line. The chemistry of the linking energy, H‐bond, and hydrophobic interactions of the BHX ligand and its mixed Cu(II) complex with Phen are revealed by molecular docking investigations with the crystal structure of S. aureus nucleoside (PDB: 3Q8U) and human prostate‐specific antigen (PDB: 3QUM). [ABSTRACT FROM AUTHOR]

The effective clinical management of cancer is entirely dependent on the detection at a suitable early time as well as on the proper diagnosis. The main aim of this review is to survey the applications of dielectric spectroscopy in the clinical cancer diagnosis and distinguishing between normal and tumor tissues. This review focuses on the recognition of the biophysical properties of normal and malignant tissues and also of biophysical changes elicited by cancers comprising (breast, liver, thyroid gland, lung, skin, bladder, uterine and ovarian, lung, and prostate) tumors. These biophysical changes are often produced because of the difference in tissue composition, blood flow, and architecture between normal and malignant cells. From the literature, it has been observed that dielectric spectroscopy method can be applied before, during or after tumor surgery; and most of the results are confirmed by conventional analysis such as histopathology. Moreover, by dielectric spectroscopy technique, dielectric parameters, especially conductivity, and permittivity were suggested to be biomarkers for the densification of cancerous patients of the previously mentioned cancer types. It could be concluded that dielectric spectroscopy rapidly provides the biophysical status of normal tissues and cancerous ones and thus can be applied effectively for the early diagnosis and detection of cancers. It could be a promising diagnostic tool in the future. [ABSTRACT FROM AUTHOR]

A new Schiff base derived from the condensation of 2‐acetylferrocene with l‐histidine was prepared and characterized using elemental analyses and spectroscopic methods. Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes of the Schiff base were prepared and characterized using various physicochemical methods such as elemental analysis, Fourier transform infrared and UV–visible spectroscopies, molar conductance, thermal analysis and scanning electron microscopy (SEM). Both ligand and complexes were investigated for their biological and anticancer activities. The elemental analyses showed that complexes were formed in a metal‐to‐ligand ratio of 1:1 stoichiometry. The spectral analyses proved that the ligand was tridentate and all complexes had an octahedral geometry, except the Zn(II) complex that was tetrahedral. SEM showed that the ligand and its Cd(II) complex were of nanometric structure. The molecular and electronic structure of the free ligand was optimized theoretically and the quantum chemical parameters were calculated. The molecular structure can be used to investigate the coordination sites and the total charge density around each atom. According to anticancer studies, Cd(II) complex was recommended to be used as anti‐breast cancer drug as it had very low IC50 (3.5 μg ml−1). Molecular docking was used to predict the binding between the free ligand and its Cd(II) complex and crystal structure of Staphylococcus aureus (PDB ID: 3Q8u), receptors of breast cancer mutant oxidoreductase (PDB ID: 3Hb5) and crystal structure of Escherichia coli (PDB ID: 3 T88) and to identify the binding mode and the crucial functional groups interacting with the three proteins. [ABSTRACT FROM AUTHOR]

An azo derivative was synthesized by coupling diazotized 2,6‐diaminopyridine with p‐dimethyl amino benzaldehyde and this new ligand formed a series of metal complexes with Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) salts. These complexes were characterized on the basis of elemental analyses, molar conductance, infrared spectroscopy, UV–Vis, 1H NMR, mass spectrometry, electronic spectra, magnetic susceptibility and ESR spectral studies, conductivity measurements, thermogravimetric analyses (TG‐DTG). The molecular and electronic structure of the azo ligand was optimized theoretically and the quantum chemical parameters were calculated. The ligand and its metal complexes were subjected to X‐ray powder diffraction study. The thermal stability of the ligand and its metal complexes was examined by thermogravimetry. The ligand and its complexes were tested for their in vitro antimicrobial activity, some of the complexes showed good antimicrobial activities against some selected bacterial and fungal strains. Anticancer activity of the ligand and its metal complexes are evaluated against human cancer (MCF‐7 cells viability). Molecular docking was used to predict the binding between azo ligand and the receptors of nucleoside diphosphate kinase of Staphylococcus aureus (3Q8U) and (3HB5) which is breast cancer mutant oxidoreductase. The docking study provided useful structural information for inhibition studies. [ABSTRACT FROM AUTHOR]

A new azo dye with N3O2 donor set of atoms has been synthesized via of 2,6-diaminopyridine with p-methoxybenzaldehyde. The molecular and electronic structure of the azo dye ligand (L) was optimized theoretically and the quantum chemical parameters were calculated. Molecular docking was used to predict the binding between L and the receptors of breast cancer mutant 3hb5-oxidoreductase, crystal structure of Escherichia coli (3 T88) and crystal structure of Staphylococcus aureus (3q8u). The newly synthesized L was used for complex formation with Cr(III), Mn(II), Fe(III), Co.(II), Ni(II), Cu(II), Zn(II) and Cd(II) ions. The nature of bonding and the stoichiometry of L and its mononuclear complexes were deduced from elemental analyses, spectroscopic, magnetic susceptibility, molar conductance, and conductivity measurements, thermogravimetric analyses and powder X-ray diffraction. Elemental analysis data show that the complexes have composition of ML type with an octahedral geometry for all the complexes. The activation thermodynamic parameters were calculated. The prepared azo dye and its metal complexes were tested against various Gram-positive and Gram-negative bacteria and a fungus. Most complexes exhibit antibacterial and antifungal activities against these organisms. Anticancer evaluation studies against standard breast cancer cell line were performed using various concentrations. The activity index was calculated. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Levofloxacin and 4‐aminoantipyrine undergo a condensation process to synthesize a novel Schiff base ligand (L). Metal complexes containing Co(II), Cu(II), Cd(II), Mn(II), Zn(II), Cr(III), Ni(II), and Fe(III) metal ions are prepared using this Schiff base ligand. The new ligand and its complexes are characterized by elemental analyses, Fourier transform infrared, mass spectrometry, ultraviolet–visible, magnetic moment, 1H‐NMR, molar conductivity, and powder X‐ray diffraction, and further thermogravimetric analysis (TG, DTA) verifies their thermal stability. The metal to ligand ratio is 1:1, according to the analytical results. Spectroscopic methods reveal that metal complexes are expected to have an octahedral geometry and demonstrate a neutral tridentate ligand behavior. It also becomes apparent from the molar conductivity values that all metal complexes are electrolytic in nature except zinc(II) and cadmium(II) complexes which are non‐electrolytes. Moreover, the bioactivity of the compounds are investigated. The antibacterial activity is investigated in relation to various Gram‐positive and Gram‐negative bacteria. The results give good indication for higher activity of the prepared compounds than the standard antibiotic drug. Also, the antioxidant activity of the newly prepared ligand and its complexes has been investigated via 2,2‐diphenyl‐1‐picrylhydrazyle (DPPH) free radical scavenging assay. The findings show that Schiff base complexes exhibit good antioxidant activity. Finally, theoretical density functional theory using density functional theory/B3LYP method and molecular docking studies with two receptors of 3T88 and 3Q8U are calculated for the investigated compounds. [ABSTRACT FROM AUTHOR]

A novel bidentate Schiff base ligand (L) and some d‐transition metal chelates (Cr (III), Mn (II), Fe (III), Co (II), Ni (II), Cu (II), Zn (II) and Cd (II)) were synthesized and characterized using various physicochemical and spectroscopic techniques like elemental analysis, IR, mass, UV–visible and thermal analysis. The spectroscopic data suggested that the parent Schiff base ligand coordinated to the metal ions through both imine nitrogen atoms. The molecular and electronic structure of the free ligand was optimized theoretically, and the quantum chemical parameters were calculated. The molecular structure can be used to investigate the coordination sites and the total charge density around each atom. The free ligand and its complexes were screened for their antimicrobial activities for various pathogenic bacteria and fungi. The anticancer activities of the free ligand, Cr (III), Mn (II) and Fe (III) complexes were screened against MCF‐7 cell line and found that Mn (II) complex has the lowest IC50 (15.90 μg/ml). Molecular docking was used to predict the binding between the free ligand with receptor of mutant human androgen (ARccr) derived from androgen‐independent prostate cancer (1GS4), crystal structure of yeast‐specific serine/threonine protein phosphatase (ppz1) of Candida Albicans (5JPE) and crystal structure of renal tumor suppressor protein, folliculin (3 V42) and to identify the binding mode and the crucial functional groups interacting with the three proteins. Highlights: Novel ferrocene‐based Schiff base ligand was prepared and its metal complexes.Many Physicochemical tools are used for characterization.The ligand is optimized theoretically using DFT calculations.Biological activity, anticancer activity and molecular docking studies are evaluated. [ABSTRACT FROM AUTHOR]

Verrucae are benign proliferations seen in skin due to infection with papillomaviruses. There are different treatment strategies for warts but all of these treatments are painful, time consuming, expensive, and recurrence is common. To evaluate and compare the efficacy of intralesional 2% zinc sulfate solution vs vitamin D3 in the treatment of plantar warts, as well as reporting the side effects. This three-armed randomized clinical trial included 105 patients presented with plantar warts divided into three groups, 35 patients per group. The first group received intralesional 2% zinc sulfate, the second group received intralesional 2% vitamin D3, and the third group received normal saline. Four sessions were done, one every 2 weeks. At the end of the study, patients showing complete response were more in zinc group (71.4%), vitamin D3 group (62.9%) compared to saline group (40%). Most of the patients in zinc group showed severe pain during injection (48.6%), most of the patients in vitamin D3 group showed mild pain (80%), while most of the patients in saline group showed no pain (57.1%). Both intralesional 2% zinc sulfate and vitamin D3 are effective in treatment of plantar warts, with zinc sulfate being more effective., (© 2020 Wiley Periodicals LLC.)